Tokkai Hei 5-39831 published in 1993 and Tokkai Hei 8-21504 published in 1996 by the Japanese Patent Office discloses a toroidal continuously variable transmission for a vehicle wherein the ratio of the rotation speed of an input disk relative to the rotation speed of an output disk, i.e., a speed ratio, is continuously varied by varying the gyration angle of a pair of power rollers gripped between the input disk and output disk.
The power rollers are respectively supported by trunnions, and when these trunnions are displaced by hydraulic actuators, the gyration angles of the power rollers change according to the displacement of the trunnions.